Personal computers and portable devices for handling copyright protected content are used.
A personal computer having content recorded therein is able to check out copyright protected content to a portable device based on the right of checkout.
The portable device is carried for use, and plays back the checked out content at a desired location.
As far as the copyright allows, content can be checked out to a portable device of another user so that the user can use the checked out content.
However, except for an approach such as inquiring acquaintances frequently, it is impossible to know the presence or details of content which others are allowed to check out.